woodson



w. E. WOODSON, JR 2,847,873

Aug. 19, 1958 PENCIL ATTACHMENT FOR ELECTRONIC DATA PICK-OFF JOY STICK Filed Aug. 25, 1955 INVENTOR.

WESLEY E. wooosolv, JR

2. AT ORNEYS United States Patent O PENCIL ATTACHMENT FOR ELECTRONIC DATA PICK-OFF JOY STICK Wesley E. Woodson, In, El Cajon, Calif.

Application August 25, 1955, Serial No. 530,646

7 Claims. (Cl. 74-491 (Granted under Title 35, U. S. Code(1952), sec. 26.6)

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

This invention relates to universal control mechanisms and more particularly to a particularly convenient hand grip attachment for a control element which is freely movable in a plane.

The joy-stick type of universal control is widely used for radio control of aircraft, gun fire director systems, controlling the screen position of an electron beam emitted by a cathode ray tube or in any situation where the position of a control element in a plane is to be translated to a pair of outputs related to the rectangular Coordinates of such position. One such device is shown in the U. S. Patent to Allen, No. 2,379,778, wherein movement of a universally mounted control lever operates a pair of potentiometers which control the fire direction of a flexibly mounted aircraft weapon. This device suffers from a fault which is common to all such devices. The final positioning characteristics and accuracy are poor due to the fact that a precise amount of small motion of the control lever is difficult to achieve and thus causes an extreme amount of positioning delay. This defeats the main advantage of the joy-stick which is speed of control. Attempts to overcome this fault by providing a movement ratio change or some type of magnetic braking have failed because the additional manipulation either causes confusion or retards the final positioning maneuver. Additionally, such attempted modifications are particularly fatiguing to the operator who must move the control against the braking action or exert additional effort to steady the device.

The present invention utilizes a manipulation to which all operators will have long been accustomed, the normal movement of a pencil in ordinary use. This movement is natural, relatively non-fatiguing and may be controlled with facility and accuracy. A pencil like arm is mounted atop the control element by means of a ball joint which is located substantially within an aperture formed in a support on which the operators arm may rest. Thus the convenient manipulation of the pencil arm which may be held in any suitable position, as in ordinary writing, will effect substantially horizontal movement of the ball joint and control element within the plane of the aperture to thereby effect the desired movement of the mechanism operated by the driving element.

It is an object of this invention to provide a control mechanism attachment particularly adapted for convenient manipulation by the hand of the operator.

Another object of this invention is the provision of a control attachment which facilitates rapid and accurate manipulation with minimum fatigue.

A further object of this invention is the provision of an attachment for a control mechanism which may be manipulated in the manner of a pencil.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same ICC 2 becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

Fig. 1 is a pictorial representation of the invention illustrating the manipulation thereof; and

Fig. 2 is an elevation view with parts broken away of the attachment and its control lever.

As illustrated in Fig. 1, a control console having a substantially flat top surface 10 contains a joy-stick or control lever 12 which is universally pivoted at 14 on a ball joint 16 or other suitable pivot structure. To that portion of the ball joint which moves with lever 12 are operably connected the output elements (not shown) of the control mechanism. Such elements may, for example, comprise a pair of potentiometers from which are to be derived voltages in accordance with the position of the control lever. The particular details of the lever, its mounting and the outputs thereof are merely incidental to this invention. However, the specific relation between a driving element 18 provided at the top of the lever and the support surface 10 are of particular importance. An aperture 20 is formed in the support 10, which is fixed with respect to the pivot 14, and the lever is arranged to have a length such that the driving element 18 is located substantially within the plane of the support 10 and substantially within the plane of the aperture 20. While the top of the lever arm, as it pivots, does have a small component of vertical motion (perpendicular to the plane of support 10) it will be seen that this vertical movement is so small as compared with the horizontal motion in the plane of the support that it may be accurately stated that the driving element 18 is freely movable horizontally within the plane of the aperture 20 and support 10.

To the driving element 18 is universally pivoted a pencil arm 22 which is shaped and manipulated in much the same manner as an ordinary writing penciL' The position of the driving element 18 (and therefore the angular position of control lever 12) is varied by simple horizonal movement of the pencil arm which is conveniently grasped and held in a position most suited to the operator.

The detailed structure of the jointed control rod of this invention is shown in Fig. 2. The control lever 12 is formed of a pair of telescopically related sections 24, 26 which may be adjustably secured together by a set screw 28 or the like whereby the length of the lever may be varied. Fixed to the top of section 26 is a driving element 18 which is merely a convenient means for fixing a ball race 30 to the lever. A ball 32 universally mounted in race 30 carries the pencil arm 22. It will be seen that the control lever length is adjustable in order to enable the positioning of the driving element 18 and the ball joint within or closely adjacent to the plane of the aperture and the plane of support 10.

While the control lever 12 is shown to be mounted by a ball joint 16, it will be readily appreciated that this invention is equally applicable to a control lever mounted as shown in the patent to Allen, supra, or to a control such as shown in the U. S. Patent to Wheeler, No. 2,455,963.

Obviously many modifications andvariations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as secifically described.

What is claimed is:

1. A control mechanism comprising a substantially fiat fixed arm support having an aperture therethrough, a control lever universally mounted on a pivot spaced from one side of said support and aligned with said aperture, and an elongated control arm universally pivoted to said lever at a point on said lever closely adjacent said aperture substantially in the plane of said support.

2. A control mechanism comprising a fixed apertured arm support, a control leverhaving a portion thereof mounted for movement relative to said-support and adjacent said aperture on a. pivot spaced from said support andaligned with said aperture, and a pencil arm pivoted at a point on said lever portion closely adjacent said aperture substantially in the plane of said support and extending beyond said support.

3. The mechanism of claim 2 wherein said lever is of adjustable length whereby the location of said lever relative to said support may be shifted axially of said lever.

4. A control mechanism comprising an apertured arm support, a jointed control rod extending through said aperture, and means pivotally mounting said rod for movement of the joint thereof closely adjacent said aperture substantially in the plane of said support.

5. A control mechanism comprising a substantially flat arm support, an aperture in said support, a control lever comprising a pair of telescopically adjustable sections, means for mounting one of said lever sections on a universal pivot spaced from said support and directly below said aperture, the other of said sections having the end thereof remote from said pivot positioned closely adjacent said aperture substantially in the plane of said support, and a pencil arm universally pivoted to said section end,

'4 whereby said control lever is moved about its pivot when said pencil arm is moved substantially horizontally at any inclination suited to the operators arm resting on said support.

6. A control mechanism comprising a fixed fiat arm support, having an aperture therethrough, a driving element freely movable substantially within said aperture, and a pencil arm pivoted to a point on said element substantially in the plane of said support.

7. A control mechanism comprising a fixed flat arm support having an aperture therethrough, driving means having at least a portion thereof freely movable substantially within said aperture and subsantially in the plane of said support, a pencil arm extending beyond said surface, and means universally pivoting said arm to said driving means portion.

References Cited in the file of this patent UNITED STATES PATENTS 1,534,680 Bump Apr. 21, 1925 1,829,037 Bobrolf Oct. 27, 1931 2,644,363 Capitani July 7, 1953 2,724,980 Russell Nov. 29, 1955 2,762,234 Dodd Sept. 11, 1956 FOREIGN PATENTS 432,192 Italy Mar. 15, 1948 

